What’s Vulnerable › Vulnerabilities

CVE-2026-84444: libheif uncompressed tiled image encoding allows out-of-bounds write

• Severity: high (CVSS 7.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-18 · updated 2026-09-22
• Weakness: CWE-787

Description

libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.23.2, when WITH_UNCOMPRESSED_CODEC is enabled, heif_context_add_image_tile() accepts an independently constructed tile whose component-plane dimensions do not match the tile geometry established by the prototype image. ImageItem_uncompressed::add_image_tile() passes that tile directly to unc_encoder::encode_tile(), which lacked the check_component_sizes() gate and sizes its output from the configured tile geometry while copying the tile's actual component-plane dimensions. An oversized component plane can therefore make unc_encoder_component_interleave::encode_tile() copy attacker-controlled data beyond the heap output buffer. This issue is fixed in version 1.23.2.

Affected products

• strukturag libheif: before 1.23.2

References

• https://github.com/strukturag/libheif/commit/e65071f59a1ac08aa1eb0d07a831deaf6bb4d03b
• https://github.com/strukturag/libheif/releases/tag/v1.23.2
• https://github.com/strukturag/libheif/security/advisories/GHSA-j264-xvrp-5v7q
• https://github.com/strukturag/libheif/security/advisories/GHSA-j264-xvrp-5v7q

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